(1. 湖南大学 材料科学与工程学院,长沙 410082;
2. 浙江大学 化学系,杭州 310027)
摘 要:
关键字: 化学转化膜;磷酸盐;锡酸盐;腐蚀;电化学阻抗谱
on ZK60 magnesium alloy
(1. College of Materials Science and Engineering,
Hunan University, Changsha 410082, China;
2. Department of Chemistry, Zhejiang University,
Hangzhou 310027, China)
Abstract:In order to enhance the anti-corrosive performance of ZK60 magnesium alloy, the chemical conversion coatings on ZK60 magnesium alloy obtained from phosphate or stannate solutions were studied. Different chemical conversion coatings were obtained by changing the processing time and temperature. The anti-corrosive performance of coatings was studied by electrochemical impedance spectroscopy and potentiodynamic polarization curves, the microscopic structures were studied by SEM. The results indicate that the charge transfer resistance(Rct) of the sample treated at 50 ℃ for 30 min is 224.03 Ω∙cm2, while the Rct of chemical conversion coatings obtained in phosphate solution at 80 ℃ for 45min is 377.67 Ω∙cm2, showing the highest anti-corrosive performance. For the stannate chemical conversion coatings, the coating obtained at 90 ℃ for 60 min has the best anti-corrosive performance with Rct value of 388.32 Ω∙cm2, but compared with the phosphate chemical conversion coatings, the difference in anti-corrosive performance is not obvious.
Key words: chemical conversion coating; phosphate; stannate; corrosion; electrochemical impedance spectroscopy